Catcher table for rolling mills



c. E. BOWRON, ET AL 2,071,509 ICATCHER TABLE FOR ROLLING MILLS I Filed Oct. 1, 1934 3 Sheets-Sheet l Feb, 23, 1937.

Feb. 23, 1937. Q BOWRON ET AL 2,071,609

CATCHER TABLE FOR ROLLING MILLs 5 Sheets-Sheet 2 Filed Oct. 1, 1954 f, E. ){a wrpn/ Feb. 23, 1937. c. E. BOWRON ET AL CATCHER TABLE FOR ROLLING MILLS Filed Oct. 1, 1934 3 Sheets-Sheet 3 Patented Feb. 23, 1937 UNITED STATES PATENT OFFICE CATCHER TABLE FOR ROLLING MILLS ware Application October 1, 1934, Serial No. 746,304

12 Claims.

Our invention relates to certain new and useful improvements in mechanical catcher tables for rolling mills and is more particularly concerned with tables comprising a bed adapted to be rocked or tilted with chains, or like conveyor elements thereon, driven so as to reverse the stock as received from the rolling mill and present it to the upper pass of a three-high mill or to return it over the upper roll of a two-high mill.

The main object of our invention is to speed up the operation of the table, it being a matter of prime importance to reduce to a minimum the time required for the return of the stock to the mill, as thereby its cooling time is lessened, the number of passes increased that can be made without reheating or, where the mill is rolling break-downs or on roughing work and the stock has to be reheated before being finished, the roughed stock will enter the reheating furnace at a higher temperature and thus will require less time to heat therein.

The stock travels with considerable speed as it is discharged onto the receiving chains from the mill rolls and it will therefore have considerable inertia. When the receiving chains are reversed, or when separate reversing chains rise and take charge of the stock on the receiving chains, it is traveling with this inertia practically unabated and such tables, as heretofore designed, have relied entirely upon the friction of the reversing chains as they move counter to the motion of the stock to bring it to rest and then start it on its return movement to the mill, but it will be obvious that there will be considerable time lost before the friction of the reversing chains can bring the stock thereon to rest and then get it under full speed back toward the mill. It is to overcome this loss that our invention is more particularly directed and this we propose to accomplish by the provision of an auxiliary set of chains or pinch rolls, or a supplemental roll bed, either live or dead, which will coact with the reversing chains to cause them when called upon to stop and return the stock to grip the latter and therefore to stop it at once and start it back rapidly. The auxiliary friction means selected may be brought into play immediately after the reversing chains act to return the stock,

or at any desired point during the rise of the table to position for returning the stock to the mill.

Our invention further comprises certain improvements in the mechanism for raising and lowering a separate set of reversing chains, which normally lie below the table element that re-- ceives the stock from the mill, crank means being provided to swing the chains through an arcuate path that will present their inner end close to the lower and upper mill passes and at the same time enable them to swing clear of the overhanging roll of a three-high mill, or upper roll of a two-high mill as they rise to take the outgoing stock from the receiving element and return it to the mill.

Our invention further contemplates the adaptation of mechanism for driving and counterweighting the cranks such as is described more in detail in a sole application of Albanus Groome Delany for a Catcher table, Serial No. 740,235.

Our invention further comprises the novel details of construction and arrangements of parts which in their preferred embodiments only are illustrated in the accompanying drawings which form a part of this specification, and in which:-

Fig. 1 is a plan view of our improved table.

Fig. 2 is a View taken on the section line Ill-II of Fig. 1, showing in side elevation the main working parts of the table.

Fig. 3 shows in plan view a modification of the upper gripping chains with a motor drive causing them to move in a manner to coact with the chains that return the stock to the mill.

Fig. 4 shows the reversing chains in elevated position assumed when the stock is returned to the mill.

Fig. 5 is a further modification of our invention showing a bed of pincher rolls instead of the chains for producing the additional friction.

Fig. 6 shows a further modification in which the pincher rolls used for the additional friction are hinged to the supporting frame.

Fig. '7 is a plan view, and

Fig. 8 a side elevation of a tilting table having a single set of reversible chains adapted to coact with the auxiliary grip chains or pincher rolls as the table tilts up and its chains, etc., are reversed to return the stock.

Similar reference numerals refer to similar parts throughout the drawings.

We have shown our invention associated with a two-high mill comprising a lower roll I and an upper roll 8, the mill housings being omitted, but it will be understood that our invention is applicable for use with other mills the rolls of which provide passes at difierent elevations.

In the embodiment of our invention illustrated in Figs. 1 to 6, the rolls, turning in the direction of the arrows, Fig. 2, discharge the stock onto a stationary bed disposed to receive it. As shown, this bed carries a set of conveyor chains 9 passing over sprockets I and II, the sprockets II being fast on a shaft I2 driven through suitable gearing by the motor I 3 which is suitably mounted on the bed. It is contemplated that these chains will be driven constantly so that in receiving the stock emerging from the mill they will have a like direction of movement. The stock as it is discharged will thus travel freely and without frictional resistance from the chains 9 until it clears the mill rolls and lies free on the table.

At this time the second set of the reversing chains I4 are brought into play and as shown these chains pass over forward idler sprockets I5 and are driven by rear sprockets I6 fast on the shaft I I which, through suitable gearing, is driven constantly by the motor I8 in a direction to return the stock to the mill. The motor I8 and sprockets I5 and I6 are all carried by a vertically adjustable frame or bed I9 independent of the bed for the chains 9 so that this bed I9 can be moved vertically in the manner and for the purposes that will now be described.

By reference to Fig. 2 it will be observed that the upper flights of the chains I4'normal1y stand below the level of the upper flights of the chains 9 and are thus out of contact with the stock while being discharged from the mill. Our invention contemplates that the moment the stock clears the mill rolls, suitable automatic agencies not shown, will cause the table I9 to be elevated, lifting its chains I4 above the level of the chains 9 and causing them to engage the stock in order to stop it and reverse it and at the same time to elevate it into proper position for its return over the rolls 8 or into the upper mill ass. This movement of the bed I9 is accomplished by the mechanism which will now be described.

At the forward end of the stationary frame or bed for the chains 9 we mount a switch box and projecting upwardly therefrom into the path of movement of the stock is a trip switch arm 2| which, the moment the stock passes it, will assume a position to energize the motor 22 which, under control of an automatic program switch 23, will turn a predetermined number of rotations in one direction and then, under control of the second trip switch arm 43, will turn back to its initial position. Such program switch mechanism is available on the market and therefore it and its conventional circuits need not be described in detail as they form no particular part of our present invention.

The trip switch mechanism 29, 2| for controlling the starting of the motor 22 may be of any character suitable to close the power circuit to motor 22 when called for by the movement of the stock therepast.

This motor 22 when energized will drive a shaft 24, extending entirely across under the catcher beds and adapted at each end to drive a crank shaft 25 through a train of gears 26, 21, 28 and 29. Each shaft 25 is mounted in suitable bearings in its respective side housing 30 and from its inner end each crank shaft has a crank arm 3| which at its free end is pivotally connected to a depending bracket 32 attached at the adjacent side to the bed I9 near its inner end.

Each shaft 25 carries a sprocket 33 which by means of a chain 34 is geared to a sprocket 35 fast on a rear crank shaft 36 similar to 25 and also mounted in a housing 30 and having its crank 3I engaging a bracket 32 near the outer end of the bed I9. This arrangement provides a four point swinging support for the movable catcher table and the cranks are given a rotation clockwise as seen in Fig. 2. They swing the bed I9 rearwardly and upwardly in an arouate path. This lifts the bed I9 in a manner to clear all of the stationary elements associated with the chains 9 and their bed and drive, and supports it in its dotted line position, in which position the cranks are substantially in dead center position. When the reversing trip switch mechanism, which will be later described, acts through switch 23 to drive the motor 22 reversely, the bed I9 will be swung back down to full line position, Fig. 2.

At the forward end of the housing 39 I mount upright posts 40 which serve as guides for a vert-ically slidable frame 4| which, as seen in Figs. 1 and 2, carries an upper set of idler chains 42 which work over sprockets 43 at each end of the frame. This frame has at each side a sleeve 4 slidable on a post 49 and normally supported by a coiled spring 45 in position for its chains 42 to clear the stock resting on the chains 9. The coiled springs 45 surround the posts 40 and rest at their ends on collars 46 fast on the posts.

As the bed chains I4 rise above the level of the chains 9 and lift the stock from engagement therewith, they will bring the stock almost immediately into engagement with the chains 42 which act after the fashion of pincher rolls to force the stock against the reversely driven chains I4 so that there will be powerful friction available to bring the stock quickly to rest and quickly to start it on its return movement to the mill. The idler chains 42 will move free with the stock while holding it pressed against the chains I4. While the stock is being brought to rest and reversed, the bed I9 is rising and the frame M is sliding upwardly with it on its guides 49 and by the time the stock has been reversed and is moving rapidly back toward the mill the chains I4 and 42 will have assumed the position in Fig. 4, and are ready to return the stock over the upper roll or into the upper pass.

The frame 4| carries a switch box 4'! having a trip switch arm which drops into the path of the returning stock and when the rear end of the latter clears it, the switch will energize the reversing switch 23 and start the reverse drive of the motor 22 and the lowering of the bed I9.

The circuits to the motor 22 will comprise a program control or a hand switch to prevent the raising of the table I9 after the rolling cycle is complete, thereby permitting the chains 9 to discharge the stock from the table.

To accelerate the starting movement of the cranks and assist in lifting the bed I9 against gravity, and to provide a brake to bring this swiftly lowering bed easily to rest, we provide fast on the outer end of each crank shaft 38 a pulley 50 having a rope, cable or chain SI passing under and partly about it and then passing over an idler 52, mounted on a bracket bearing 53, and thence downwardly through a main counterweight 54 to engage a small counterweight 55. This apparatus is duplicated on both sides and it will be noted that the main counterweight 54 extends entirely across under the bed.

The counterweight means will acts as follows:With the bed I9 in lowered position the counterweights 54 and 55 stand as shown in Fig. 2 and both weights exert a pull tending to swing the bed I9 upwardly. On starting the I9 is swung upwardly and its upward motion, the counterweights fall and when the table is gotten under full speed and is about one-half way up, the counterweight 54 comes to rest on the seat 56 and thereafter will exert no effect on the rising bed [9 while the counterweights 55 drops on down to hold the requisite tension on the cables 5|. When the bed l9 starts on its down travel the counterweights 55 only are first lifted but, when the bed is half way down, they pickup the main counterweight 54 whichthus resists the downward momentum of the bed and brings it quietly to rest in lowered position. a

A spring 51 may be interposed on the cables between each counterweight 55 and the main counterweight 54 to take up the jar when the counterweight 54 is picked up. v I

In Fig. 3 we show a modification of our-invention in which the frame 4| has mounted thereon a motor 58 which drives a shaft 59 carrying the front sprockets 60 so as to'cause the chains 42 to travel so that their lower flight will move in the same direction as-the upper flight of the chains l4, i. e., toward themill. In this arrangement the chains 42 will first act as a brake to check quickly the stock and then to enact with the chains l4 to effect a quick return of the stock to the mill. The motor is controlled by circuits not shown which may provide for its continuous operation or for starting it up at any desired point in its upward movement with the chains vl4 when the chains l4 and 42 will grip the stock between them without any relative or counter-movement such as would exist if the two moving sets of chains gripped the stock while the bed [9 was swinging away from the mill as it will during the lower quadrant .of its lifting movement.

In Fig. 5 we show the frame 4| and chains 42 replaced by a roll bed 63 having the sleeves 44 as on the frame 41 slidable on the posts 49 and having a series of idler pincher rolls 64 which are loosely mounted for vertical play in slots 65 in each side of the frame.

In Fig. 6 we show a frame 66 with the sleeves 44 and a series of pincher rolls 6'! swung by arms 68 from the frame 66 with stops 69 to limit the up travel of the arms while permitting the pincher rolls to accommodate themselves to different shapes and conformation of the stock. Both of the modifications shown in Figs. 5 and 6 will rest upon the supporting springs 45 as in Fig, 1 and will slide freely on the posts 49 in the manner already described, applying a pincher action which will produce the requisite frictional engagement between the stock and the chains I4 to insure the rapid manipulation contemplated. J

The beds for the two setsof chains may have side stock guides if desired, and it simplifies matters for each bed to carry its motor drive for its chains. We prefer for the stationary bed to have chains or live rolls but in many cases this may not be necessary as the stock will be discharged by the mill rolls onto this bed.

In the embodiment of our invention shown in Figs. '7 and 8, we use a table carrying the set of chains 9 driven in the manner described by the motor I3, but instead of making this table stationary as in Fig. 1, we provide it near its center with depending brackets 10 on each side and mount it to tilt by means of a shaft H journaled in the bearing brackets 12 which are suitably anchored to the foundation and which support the table at its center substantially level with the center of the middle roll 13 of .a three-high mill comprising a lower roll 14 and an upper roll 75. The motor l3 in this arrangement is set below the bed plate 16 of thetable and has its control circuits 1'! leading to a suitable control mechanism, not shown. Attached to the underside of the bed plate 15 near its end remote from the mill is a bracket 18 connected by a link 19 to a bell crank mounted on a'bracket 8! and connected by a link 82 to the. piston 83 of a fluid pressure motor 84. This motor is controlled bya rotary valve 85 through link .35 pivotally connected to a rod 8'! which in turn is connectedto the core 88 of a solenoid 89. that is controlled by a circuit 90. A spring 9i, acting between a fixed bearing 92 and a collar on the rod 81, normally hold the fluid pressure on the cylinder 84 through a pipe 94 in such manner as to tilt the table as shown in Fig. 8, which is its position for receiving the stock from the lower pass of the mill. It will be observed that the chains tilt down.- wardlytoward the lower pass and approach it closely so that the stock can be suitably guided thereonto by a stationary guide 95 and will pass onto the chains 9 which at the time, according to the control of the circuit 11, may be moving counter to the oncoming stock or may be still or moving in the same direction therewith.

When the-stock has emerged from the lower pass and rests entirely on the table 9, its control circuits act to tilt the table upwardly and, if its chains have been traveling concurrently with the stock, their direction will be reversed to start the stock back toward the mill so that by the time the table assumes position opposite the upper pass the stock will be ready for delivery thereinto.

The stock will pass freely onto such a table and will have considerable momentum. We provide means to grip the stock to stop it and quickly return it to the mill comprising the frame 4 I, carrying the chains 42 as in Fig. 4, attached at each end to a pair of crank arms 96 which are journaled on the shaft H with their lower end depending in position each to engage a coil compression spring 91 interposed between it and a spring seat 98 fast on the base of its respective bearing 12. These springs, acting through the cranks 95 at each side, serve normally to support the chains 42 clear of the chains 9 with which they stand in line. As the table tilts upwardly however the stock on its chains 9 will engage the chains 42, which may be live or dead chains as desired, and they act as a gripping or pincher means to cause the stock to be firmly engaged between the sets of chains, thereby insuring its more rapid stoppage and return to the mill.

The pressure to be exerted by the chains 42 upon the stock can be increased by the provision of springs 99 carried by spring brackets I55! which will engage the depending crank arms as the latter rock and oppose the upward movement of the frame 4l thereby imposing additional pressure on the stock.

As a preferred means for controlling the various circuits that operate the tilting table and its chains, we provide a light sensitive means controlled by the passage of the stock for starting and stopping the various controls of the table both to elevate and lower it and to reverse its chains either to return the stock to the mill or to discharge it after the rolling operation is completed. Such various controls are more fully described in a companion application filed in the names of Albanus Groome Delany and Guy Newton Hughes, Serial No. 609,064.

In the embodiment shown, the switch mechanism for controlling the various circuits is responsive to light sensitive means illustrated as a photoelectric cell l0! and a cooperative light source cell I02 is connected by a circuit 103 to suitable switch mechanism, not shown, which in turn controls the circuits 11 and 90. The lamp is so arranged that its ray of light will pass between the shafts and. I05 for the sprockets at the mill end of the chains 9 and 42 and will impinge upon the photoelectric cell In! until interrupted by the passage of the stock.

When the stock passing onto the table moves out of the path of. the ray of light the control mechanism will be set in motion to tilt the table upwardly and eifect a reversal of the stock and its return to the mill, and in like manner, when the stock again intercepts the light ray and. moves past it on its return travel, the agencies are set in motion to lower the table to its receiving position, ready torepeat the cycle, or if desired program switch means can be provided, which after a predetermined number of passes will effect the discharge of the finished stock.

In the operation of all of the embodiments of our invention shown, the stock is permitted to pass freely on to the table, but the moment its trailing end has cleared the control point the tilting or raising of the table commences, the return of the stock is expedited by the auxiliary friction chains or rolls that are engaged by the rising table to enable its chains effectively to grip and quickly to return the stock to the mill.

While we have shown our invention in several forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications, without departing from the spiritthereof, and we desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

What we claim is:

1. In a mechanical catcher table for rolling mills, a table disposed to receive the stock discharged by the mill, a second table carrying live conveyor means driven in a direction to return stock to the mill, means automatically responsive to passage of stock on to the receiving table to produce relative movement of said tables to shift the stock from the receiving to the returning table, and means to hold the stock firmly engaged by said live conveyor means.

2. In a mechanical catcher table for rolling mills, a table disposed to receive the stock discharged by the mill, a second table carrying live conveyor means driven in a direction to return stock to the mill, said second table being disposed beneath the first table when stock is being received, means to produce relative movement of said tables to shift the stock from the receiving to the returning table operative upon the passage of stock on to the receiving table, and means brought into play by said movement to hold the stock firmly engaged by said live conveyor means.

3. In a mechanical catcher table for rolling mills, a table disposed to receive the stock discharged by the mill, a second table carrying live conveyor means driven in a direction to return stock to the mill, said second table being outside the path of stock being received, means to produce relative movement of said tables operative upon the passage of stock on tothe receiving table to shift the stock from the receiving to the returning table, and means disposed in the path of movement of the returning table and movable therewith which are adapted to hold the stock firmly engaged by said live conveyor means.

4. In a mechanical catcher table for rolling mills, a table disposed to receive the stock discharged by the mill, a second table carrying live conveyor means driven in a direction to return stock to the mill, said second table being disposed out of the path of stock being received, means to produce relative movement of said tables responsive to the passage of stock from the rolls to the receiving table to shift the stock from the receiving to the returning table, and means comprising a second stock returning conveyor means mounted for vertical adjustment in the path of movement of the returning table and adapted to grip the stock between the two returning conveyor means.

5. In a mechanical catcher table for rolling mills, a table disposed to receive the stock discharged by the mill, a second table carrying live conveyor means driven in a direction to return stock to'the mill, said second table having its upper surface beneath that of the first table when stock is being received, means to produce relative movement of said tables operable when stock has passed from the rolls to the receiving table to shift the stock from the receiving to the returning table, and means comprising a vertically movable frame having pincher rolls disposed in the path of movement of the stock returning conveyor means.

6. A catcher table for rolling mills, comprising a bed disposed to receive stock from the mill rolls, a conveyor means normally disposed below the bed level, automatic means to elevate said conveyor means responsive to passage of stock from the rolls to the receiving bed, to engage and lift the stock from said bed into position for its return to the mill, means to drive said conveyor means in a direction to return the stock to the mill, and means to press the stock firmly into frictional engagement with said conveyor means to effect a quick arrest and return thereof to the mill.

'7. A catcher table for rolling mills, comprising a bed disposed to receive stock from the mill rolls, a conveyor means normally disposed below the bed level, means responsive to passage of stock from the rolls to the receiving bed, to elevate said conveyor means to engage and lift the stock from said bed into position for its return to the mill, means to drive said conveyor means in a direction to return the stock to the mill, and means disposed to engage the stock after it has been lifted from said bed and press it against said conveyor means.

8. A catcher table according to claim 6, in which the elevating means for the return conveyor means comprises two coordinated cranks at each side, all the cranks having a common drive adapted to swing said conveyor means in an arcuate path away from the mill in shifting it from lower to upper position and vice versa.

9. In a mechanical catcher table for rolling mills, a stationary table element having stock receiving chains and means to drive same with their upper flight moving away from the mill, a vertically movable table element having its upper surface disposed'below that of the first table when receiving stock and having chains driven reversely to the first, means responsive to the passage of stock from the rolls to the receiving bed to elevate said latter table so as to support the stock on its chains in elevated position ready for its return to the mill, and friction means operative against the elevated stock to press it against said reversely driven chains.

10. A mechanical catcher according to claim 9, in which the table elevating means comprise cranks driven in a direction to swing the movable table in an arcuate path away from the mill to clear its rolls.

11. A mechanical catcher according to claim 9, in which the table elevating means comprise cranks driven in a direction to swing the movable table in an arcuate path away from the mill to clear its rolls with the table approaching dead center position with reference to said cranks in its upper and lower positions.

12. A mechanical catcher according to claim 9, in which the table elevating means comprise cranks driven in a direction to swing the movable table in an arcuate path away from the mill to clear its rolls with counterweight means coordinated with the cranks to assist at the start of the table lifting motion and to check the com- 10 pletion of the table lowering motion.

CHARLES E. BOWRON. ALBANUS G. DELANY. 

